Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
  • F28D20/00—Heat storage plants or apparatus in general; Regenerative heat-exchange apparatus not covered by groups F28D17/00 or F28D19/00
  • F28D20/0056—Heat storage plants or apparatus in general; Regenerative heat-exchange apparatus not covered by groups F28D17/00 or F28D19/00 using solid heat storage material
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F28—HEAT EXCHANGE IN GENERAL
  • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
  • F28D17/00—Regenerative heat-exchange apparatus in which a stationary intermediate heat-transfer medium or body is contacted successively by each heat-exchange medium, e.g. using granular particles
  • F28D17/005—Regenerative heat-exchange apparatus in which a stationary intermediate heat-transfer medium or body is contacted successively by each heat-exchange medium, e.g. using granular particles using granular particles
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/14—Thermal energy storage

Definitions

• the technical field of the invention is that of energy saving, more particularly of the reuse of thermal energy.
• the present invention relates to a device for thermal storage, that is to say of calories or frigories, with a view to their subsequent return.
• these devices comprise a container, for example a metal container, comprising a material with thermal inertia provided for storing and releasing heat.
• a fluid inlet interface making it possible to introduce a fluid into the device in order to achieve a heat exchange between the fluid and the thermal inertial material, and a fluid outlet interface for extracting the fluid from the device after said said device. heat exchange.
• the use of a thermal storage device conventionally comprises two phases.
• a hot fluid is circulated in the device.
• a heat exchange takes place between the hot fluid and the thermal inertial material, transferring part of the calories from the hot fluid to the thermal inertial material.
• a cold fluid is circulated in the device comprising the thermal inertial material loaded with calories. Heat exchange takes place between the thermal inertia material and the cold fluid, transferring part of the calories from the thermal inertia material to the cold fluid which then heats up.
• the thermal inertial material can take the form of a plurality of independent storage elements, conventionally balls of a refractory material, for example ceramic balls. This advantageously makes it possible to obtain a large contact surface between the fluid and the thermal inertial material.
• the container often expands under the effect of heat, resulting in an increase in the internal volume of the container. If the coefficient of thermal expansion of the container is greater than that of the storage elements, a free volume is created when said container expands, and the storage elements can then be reorganized so as to occupy the additional space freed by the expansion of the container. In other words, a settlement of the storage elements occurs in the container.
• a first unfavorable consequence of the compaction of the storage elements occurs during the cooling of the container during which the container tends to retract in order to resume its initial volume.
• the new distribution of storage elements mechanically constrains the container by opposing its retraction, thus generating mechanical stresses liable to damage the structure of the container.
• a second unfavorable consequence of the settlement is an uneven distribution of the storage elements in the container.
• the distribution of the storage elements becomes heterogeneous, for example a greater density in the lower part of the tank, and less in the upper part of the tank. Consequently, the space between the storage elements is greater in the upper part of the tank and less important in the lower part of the tank.
• An existing solution to avoid the settling of the storage elements consists in thermally insulating the storage elements from the wall of the container in order to limit the expansion of the wall, for example by lining the inside of the container with a thermally insulating layer .
• this solution is expensive and complex to implement.
• the invention offers a solution to the problems mentioned above by proposing a new structure for a heat storage device in which the settlement of the storage elements is limited by simple means.
• a calorie / frigory storage device comprising a container comprising a wall comprising a first interface adapted to the entry of a fluid into the device and a second interface adapted to the outlet of the fluid. of the device, a plurality of storage elements arranged in said container and configured to store calories / frigories supplied by the fluid.
• the container comprises at least one perforated internal wall comprising openings of dimensions smaller than the dimensions of the storage elements and defining a first compartment and at least a second compartment in the container, the plurality of 'storage elements being distributed in the first compartment and in said at least one second compartment.
• the absolute change in volume in each compartment is less than the absolute change in volume of the entire device.
• the space freed up in each compartment by the expansion of the container is therefore advantageously insufficient to allow a complete reorganization of the storage elements.
• the perforated wall advantageously makes it possible to maintain good circulation of the fluid while reducing the mobility of the storage elements.
• the system comprises a plurality of these perforated walls.
• the device may include a thermally insulating layer arranged around the wall of the container.
• thermally insulating layer advantageously makes it possible to avoid heat loss to the outside of the device and therefore to improve its efficiency.
• the container may be of cylindrical shape, said at least one internal wall being perpendicular to the axis of the cylinder and / or said at least one internal wall being parallel to the axis of the cylinder.
• a cylinder is understood here as a solid generated by a line segment, called a generating line, which moves parallel to an axis between two parallel fixed planes called the bases of the cylinder.
• a cylinder can have discoidal bases, ellipsoidal bases or bases of any shape.
• a cylinder can also have polygonal bases and in this case the cylinder is a prism.
• a cylinder with hexagonal bases allows optimal stacking of the storage elements.
• a cylinder whose bases are perpendicular to the generating line is a right cylinder.
• the width of each compartment may be less than 25 times the maximum dimension of a storage element.
• Each storage element has a maximum dimension of between 10 millimeters and 50 millimeters.
• the device further comprises at least one filling opening made in the wall of the container at the highest level of the wall of the container. This filling hole makes it possible to fill the container with the storage elements.
• the device comprises at least one drain hole made in the wall of the container at the lowest level of the wall of the container.
• a condensate management system comprising a siphon comprising a pipe having a first end adapted to be coupled to a drain hole and a second end submerged in a drain pan, the siphon being configured to allow passage of liquid from the first end of the pipe to the drain pan and to prevent passage of liquid from the drain pan to the first end of the pipe.
• each drain hole can be coupled to the drain pan via the siphon, the first end of which is coupled to said at least a drain hole, the siphon being configured to allow a passage of liquid, for example a liquid formed from condensate, from the container to the drain pan and to prevent a passage of liquid from the drain pan to the container.
• a passage of liquid for example a liquid formed from condensate
• the presence of the siphon advantageously makes it possible to prevent the drain holes from being in the open and the liquid present in the tank from rising into the device.
• the drain pan may include automatic filling means of said tank suitable for pouring a filling liquid into the drain tank as long as the amount of filling liquid in the drain tank is below a determined threshold.
• At least one interface comprises a diffuser comprising a plurality of coaxial frustoconical walls and which is configured to circulate the fluid through spaces provided between the walls between a narrow end of the diffuser remote from the container and a wide end of the diffuser coupled to the container.
• the diffuser When the diffuser is placed on the first interface allowing the entry of the fluid, the diffuser advantageously makes it possible to diffuse the fluid in the container, that is to say to distribute it throughout the internal volume of the device and therefore improve heat transfer. When the diffuser is placed on the second interface allowing the fluid to exit, this allows better flow of the fluid to the outside of the device.
• Figures 1 to 5 show embodiments of a device according to the invention.
• Figure 1 is a schematic representation of a first non-limiting embodiment of a calorie and / or frigorie storage device 100 according to the invention.
• the storage device 100 comprises a rigid container, for example a container comprising a metal wall 102, here a steel wall whose thickness is between two and eight millimeters, and preferably five millimeters thick.
• the container has the shape of a circular right cylinder and a first flat end 10 of the container forms a first base of the cylinder and a second flat end 11 of the container forms a second base of the cylinder.
• the container could just as well have any other shape, such as a non-straight cylinder, and in particular a prismatic shape, for example a parallelepiped.
• the device 100 comprises an internal volume VI suitable for the circulation of a fluid, in particular a heat transfer fluid, and delimited by an internal surface SI of the device 100.
• the internal surface SI is defined by the metal wall 102.
• the internal volume is here a cylindrical volume.
• the device 100 further comprises a plurality of storage elements 104, arranged in the internal volume VI of the container so as to occupy the maximum internal volume VI.
• the storage elements 104 are refractory ceramic balls 20 millimeters in diameter.
• This refractory ceramic is manufactured from conventional raw materials such as alumina or bauxite, or from inorganic secondary raw materials, in particular steel slag, coal ash or biomass ash.
• the storage elements could have any other shape, any other dimension, in particular a dimension between 10 millimeters and 50 millimeters, and be made of any other known refractory material.
• FIG. 1 For the sake of simplification, a single storage element 104 is referenced in FIG. 1.
• the first interface 110 and the second interface 111 respectively comprise a first orifice 112 and a second orifice 113 formed in the metal wall 102 of the container, respectively at the level of the first flat end 10 and at the level of the second flat end 11 so that the first orifice 112 and the second orifice 113 are facing each other.
• the first orifice 112 and the second orifice 113 are suitable for fixing a conduit for circulating fluid, in particular a gas.
• Achieving the first and the second interface facing each other on opposite walls of the container is advantageous because it allows better circulation of the fluid through the device 100, but it would be quite possible that the two interfaces would not are not facing each other, and in particular are made on non-opposing sides of the container.
• the first interface 110 is here suitable for fixing a hot smoke inlet duct from an industrial oven
• the second interface 111 is here suitable for fixing a outlet duct for said cooled industrial smoke.
• first interface 110 and a single second interface 111 are described here, it would be quite possible for the device to include several first interfaces and several second interfaces, and preferably a number of first interfaces equal to the number second interfaces.
• first interfaces would all be carried out at the level of the first flat end 10 and the second interfaces would all be made at the level of the second flat end 11.
• the device 100 here comprises a perforated internal wall 105, for example here a circular metal grid whose bars define square openings of 15 millimeters on the side.
• the perforated wall 105 is in the form of a plate comprising a plurality of holes uniformly distributed over its surface. These plates are for example and in a nonlimiting manner of the industrial grating type made of the same material as the container.
• the wall is arranged in internal volume VI so as to be parallel to the flat ends 10 and 11, that is to say perpendicular to the axis of the cylinder formed by the container, at an equal distance from the first flat end 10 and the second flat end 11.
• the wall 105 is here dimensioned so that its diameter is slightly less than the internal diameter of the container. Typically, the diameter of the wall 105 is 5 mm less than the internal diameter of the container to avoid mechanical stresses between the wall 105 and the container. In addition, the wall 105 is held by at least one stopper (not shown) welded to the internal face of the wall of the container.
• the grid divides the internal volume VI of the device into a first compartment 13i and into a second compartment 13 2 .
• a first part of the plurality of storage elements is located in the first compartment, and a second part of the plurality of storage elements is located in the second compartment. Since the dimensions of the storage elements 104 are greater than the dimensions of the openings of the perforated wall 105, the storage elements located in the first compartment 13i cannot pass into the second compartment 13 2 , and the storage elements located in the second compartment 13 2 cannot pass into the first compartment 13i.
• each of the compartments here has a volume equal to half of the internal volume VI of the container 100, a variation of a given volume of the container will correspond to a variation of a volume two times less in each of the compartments. .
• the storage elements in each compartment therefore have half the space to reorganize themselves, which advantageously limits the settlement.
• the invention is not limited to a device comprising a single perforated internal wall.
• the device can comprise a plurality of perforated internal walls defining a plurality of compartments.
• the device 100 comprises four perforated internal walls 105i, 105 2 , 1053, and 105 4 dividing the internal volume VI into five compartments 13i, 13 2 , 133, 13 4 , 13 5 , of identical dimensions and geometry .
• the five perforated walls are identical to the perforated wall described above in connection with Figure 1, and are distributed in the container so as to define five compartments of identical dimensions, the plurality of storage elements being distributed equally in the five compartments.
• each of the compartments has a volume equal to one fifth of the total volume of the container, an absolute variation of a given volume of the container will correspond to a variation of a volume five times less in each of the compartments.
• a 316 stainless steel container with a length of four meters at 25 ° C, and whose thermal expansion coefficient is 18 * 10 _6 / ° C extends 37mm when its temperature reaches 500 ° vs.
• the variation in internal length of a compartment is therefore 9.25 mm.
• the thermal expansion of the storage elements in a compartment, the coefficient of thermal expansion of which is 2.4 * 10 6 / ° C, is 1.2 mm. There is therefore a longitudinal distance released in each compartment of 8.05 mm.
• the latter must have a diameter greater than this released distance, and ideally a diameter at least 1.5 times greater than the longitudinal distance released in each compartment, ie at least 12 , 75 mm in the latter case.
• the device 100 comprises a thermally insulating layer 108 disposed outside the container around the metal wall 102 so as to cover its outer surface.
• the thermally insulating layer 108 here comprises an assembly of rock wool panels. It has a thickness of 300 millimeters.
• the thermally insulating layer 108 to include any other insulating material, for example a material chosen from glass wool, ceramic wool, calcium silicate panels or vermiculite panels, and have any other thickness, for example a thickness between 100 millimeters and 300 millimeters.
• the thermally insulating layer 108 advantageously makes it possible to avoid heat loss to the outside of the device and therefore to improve the efficiency of heat energy storage.
• the first interface 110 comprises a first diffuser 20 coupled to the first orifice 112 made in the metal wall 102 and in the thermally insulating layer 108 and the second interface 11 comprises a second diffuser 21 coupled to the second orifice 113 made in the metal wall 102 and in the thermally insulating layer 108.
• the first diffuser 20 and the second diffuser 23 are here identical, so only the first diffuser 20 will be described here for the sake of brevity. .
• the first diffuser comprises three frustoconical walls 200, 201, 202 arranged coaxially around a portion of the axis of the cylinder formed by the container extending between a narrow end 21 of the first diffuser 20 and a wide end 22 of the first diffuser 20, the narrow end 21 having a diameter smaller than the diameter of the wide end 22, here a diameter seven times smaller.
• the wide end 22 is coupled to the first orifice 112 which here has a diameter equal to the internal diameter of the device, that is to say to the diameter of the internal volume VI of the tank.
• the narrow end 21 of the diffuser 20 is remote from the container and adapted to the attachment of a conduit for circulating a fluid.
• a fluid circulating in the first diffuser 20 for example here from the narrow end 21 to the wide end 22 and the internal volume VI of the device 100, will circulate in the spaces arranged between the walls 200, 201, 202 up to the internal volume VI of the device.
• the fluid will therefore advantageously be diffused so as to occupy the entire internal volume VI during its circulation.
• the fluid circulating in the second diffuser 23 will converge from the narrow end of the second diffuser 23, of larger diameter, to the narrow end of the second diffuser 23, of smaller diameter.
• the second diffuser 23 advantageously makes it possible to facilitate the exit of the coolant from the device.
• the device 100 has five walls 105i,
• Two walls 105i and 105s are located respectively at the level of the first orifice 112 and at the level of the second orifice 113 in order to maintain the storage elements in the internal volume VI of the device 100.
• Three walls 105 2 are located respectively at the level of the first orifice 112 and at the level of the second orifice 113 in order to maintain the storage elements in the internal volume VI of the device 100.
• 105 3 , 105 4 divide the internal volume VI into four compartments, that is to say into a first compartment 13i, a second compartment 13 2 , a third compartment 133 and a fourth compartment 13 4 .
• the device 100 comprises a condensate management system 300.
• the condensate management system 300 is here coupled to a storage device 100 according to the embodiment described in FIG. 4, but could be coupled to any storage device, in particular a storage device 100 according to any one of the embodiments of the invention.
• each compartment has a drain orifice.
• the first compartment 13i has a first drain hole 30i
• the second compartment 13 2 has a second drain hole 30 2
• the third compartment 13 3 has a third drain hole.
• drain 30 3 and the fourth compartment 13 4 has a fourth drain hole 30 4 .
• the drain openings 30-i, 30 2 , 303, 30 4 are made in the metal wall 102 and in the thermally insulating layer 108, at the lowest level of the device 100.
• the condensates resulting from the cooling of the fluid in contact with the colder storage elements flow by gravity towards the bottom of the internal volume VI and are evacuated by the condensate management system 300.
• a slight overpressure for example of the order of 20 millibars is applied inside the container, so as to promote the circulation of the heat transfer fluid.
• the device also has a discharge mode of operation, during which passes a cold heat transfer fluid to recover the heat stored in the storage elements. In this discharge mode of operation, a slight depression, for example of the order of 20 millibars, is applied inside the container, so as to promote the circulation of the cold fluid.
• the first, second, third and fourth drain orifices 30i, 30 2 , 303 and 30 4 are here respectively coupled to a first, second, third and fourth pipes 32i, 32 2 , 323 and 32 4 , each pipe being coupled to its respective port by a first end and has a second end immersed in a drain pan 34 filled with a filling liquid 340, here some water.
• the drain pan 34 is located at a lower level than that of the orifices 30i, 30 2 , 303 and 30 4 .
• Each pipe is here doubly bent and forms with the drain pan 34 a siphon. There is therefore a column of water in each pipe submerged in the tank 34, the height of which is sufficient to compensate for the overpressure in the container in the event of the latter being loaded, or the vacuum in the container in the event of discharge of the latter.
• the siphon is also configured to allow the flow of a liquid formed of condensate from the internal volume VI of the device 100 towards the drain pan 34, and to prevent the rise of liquid from the drain pan 34 to the internal volume VI of the device.
• the condensate management system 300 comprises an automatic means for filling the tank 35 comprising a level detector 350 and a filling liquid inlet 351, here a water inlet, the level detector 350 being configured to control the opening of the liquid inlet 351 when the filling liquid level 340 in the tank 34 is below a threshold , and to control the closing of the liquid inlet 351 when the level of filling liquid 340 in the tank 34 is equal to or greater than the threshold.
• the threshold is equivalent to this pressure difference in the height of the water column (that is, i.e. 200 mm), to which a safety margin of 50 mm water column height is added.
• the threshold prevents the rise of liquid from the drain pan 34 to the internal volume VI of the device 100 in the event of depression of the container, and it also avoids purging the pipes 32i, 32 2 , 32 3 and 32 4 in the event of overpressure in the volume VI of the device 100, which would have the effect of creating a hot air leak through the drain openings 30i, 30 2 , 303 and 30 4.
• a device 100 comprising the condensate management system 300 may include a single drain orifice in each compartment, several drain orifices in each compartment or even one or more orifices in only some of the compartments.
• the cylindrical container 100 when it has a length greater than its diameter, is disposed horizontally on the ground, that is to say that the directrix of the cylinder is oriented parallel to the plane in which extends the ground on which the container 100 rests.
• This arrangement of the container 100 offers the double advantage on the one hand of facilitating the transport of the container 100 and on the other hand of limiting the height of the distribution of the storage elements 104. In fact, the force induced by gravity and exerted by the Storage elements 104 on the bottom wall of the container 100 is limited.
• a container comprises perforated plates extending perpendicularly to the longitudinal axis of the container, and which are distributed in the top volume and in the bottom volume of the container. Like the perforated plates, this horizontal wall rests on supports integral with the wall of the container.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Filling Or Discharging Of Gas Storage Vessels (AREA)

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• 2019
  • 2019-08-08 FR FR1909070A patent/FR3099821B1/fr active Active
• 2020
  • 2020-08-06 EP EP20765203.3A patent/EP4010651A1/de active Pending
  • 2020-08-06 US US17/633,303 patent/US12078425B2/en active Active
  • 2020-08-06 CN CN202080056139.1A patent/CN114270128A/zh active Pending
  • 2020-08-06 WO PCT/EP2020/072173 patent/WO2021023834A1/fr active Search and Examination

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